Installing And Other Problems

Okay Heres The Problem(s)...
I Can't Install 7.0.470.000 it says initializing. Verifying Installed blah blah (sorry not meaning to sound rude) then either that freezes and sits there till i go into task manager or it pulls this mini screen saying it encountered an error and had to close then half the time true vector then encounters a problem..Can You Help Me With This?? [ive tried the uninstall thing and i ended up losing internet and not able to reinstall it so i had to do so much and im back to this again, so either could someone help me install it and find a new way to get the update or maybe some easy-to-do uninstall thats succesful]
Second. i Cant change my license i tried to put the new one i bought today and then it says okay it was changed then when i go back to change license its the old one again..And When i go to Check for Product Updates its all greyed out and i cant choose to automatic or manual so i cant ask it to download the new one (Which doesnt work anyway)
Then it says That Registration is always pending...
Yeah Theres Alot of Problems i have, sorry So Could You Help Me Please? ive been trying to figure it out for about 2 months and ive finnally given up